With the development of Internet technologies, more and more content is transmitted and accessed over the Internet. Currently, the browser/server (B/S) application mode is typically employed to transmit and access content over the Internet. Specifically, the content is stored on a Web server, a Hypertext transfer Protocol (HTTP)-based platform, in the form of files, and transferred to a client using HTTP. After being processed by a client browser, the content is displayed on the client.
However, endless viruses and Trojan horses deteriorate security of the transmission and access of the content over the Internet, resulting in economic and mental losses. A commonly used solution to such problems is that the client identifies viruses and Trojan horses hidden in the content during transmission by using such installed software as virus library and firewall.
Nevertheless, the software such as virus library and firewall installed on the client increases load of the client, and increases costs and workload for maintaining and upgrading such software. Especially, such problem becomes severe with respect to a client having limited storage capacity and event processing capability, for example, mobile phones.